diff -r b5530669ef70 Lib/tempfile.py
--- a/Lib/tempfile.py	Wed Sep 04 20:52:14 2013 +0200
+++ b/Lib/tempfile.py	Thu Sep 05 15:02:18 2013 +0300
@@ -326,15 +326,12 @@
     """Temporary file wrapper
 
     This class provides a wrapper around files opened for
-    temporary use.  In particular, it seeks to automatically
-    remove the file when it is no longer needed.
+    temporary use.
     """
 
-    def __init__(self, file, name, delete=True):
+    def __init__(self, file, name):
         self.file = file
         self.name = name
-        self.close_called = False
-        self.delete = delete
 
     def __getattr__(self, name):
         # Attribute lookups are delegated to the underlying file
@@ -356,36 +353,8 @@
     def __iter__(self):
         return iter(self.file)
 
-    # NT provides delete-on-close as a primitive, so we don't need
-    # the wrapper to do anything special.  We still use it so that
-    # file.name is useful (i.e. not "(fdopen)") with NamedTemporaryFile.
-    if _os.name != 'nt':
-        # Cache the unlinker so we don't get spurious errors at
-        # shutdown when the module-level "os" is None'd out.  Note
-        # that this must be referenced as self.unlink, because the
-        # name TemporaryFileWrapper may also get None'd out before
-        # __del__ is called.
-        unlink = _os.unlink
-
-        def close(self):
-            if not self.close_called:
-                self.close_called = True
-                self.file.close()
-                if self.delete:
-                    self.unlink(self.name)
-
-        def __del__(self):
-            self.close()
-
-        # Need to trap __exit__ as well to ensure the file gets
-        # deleted when used in a with statement
-        def __exit__(self, exc, value, tb):
-            result = self.file.__exit__(exc, value, tb)
-            self.close()
-            return result
-    else:
-        def __exit__(self, exc, value, tb):
-            self.file.__exit__(exc, value, tb)
+    def __exit__(self, exc, value, tb):
+        self.file.__exit__(exc, value, tb)
 
 
 def NamedTemporaryFile(mode='w+b', buffering=-1, encoding=None,
@@ -419,8 +388,18 @@
     (fd, name) = _mkstemp_inner(dir, prefix, suffix, flags)
     file = _io.open(fd, mode, buffering=buffering,
                     newline=newline, encoding=encoding)
+    if _os.name != 'nt' and delete:
+        oldclose = file.close
+        def close():
+            if not file.closed:
+                try:
+                    oldclose()
+                finally:
+                    _os.unlink(name)
+                    file.close = oldclose
+        file.close = close
 
-    return _TemporaryFileWrapper(file, name, delete)
+    return _TemporaryFileWrapper(file, name)
 
 if _os.name != 'posix' or _os.sys.platform == 'cygwin':
     # On non-POSIX and Cygwin systems, assume that we cannot unlink a file